The present invention relates to optical devices that enable a viewer to observe objects at night or during other low-light conditions. More particularly, the present invention relates to a handheld binocular system that can be manufactured at low cost for sale to the general public.
Night vision devices are widely used in the military to provide soldiers, aviators and sailors with the ability to view objects at night or during other low light conditions. As a result, many night vision devices are currently being manufactured according to exacting military specifications and designs. Similarly, many such night vision devices are being manufactured for specific military applications such as part of the sights of various weapons or as part of goggle assemblies that attach to an aviator""s or soldier""s helmet. As a consequence, many of the night vision devices currently being manufactured are neither affordable nor easily adapted to non-military uses by the general public.
Night vision devices typically include an image intensifier tube that converts infrared energy into visible light. Such night vision devices typically require sophisticated power supplies and circuitry to control the operation of the image intensifier tube and sophisticated optical arrangements that direct the infrared energy into the image intensifier tube and visible fight away from the image intensifier tube. In military applications, the various military personnel are trained in how to use and adjust the night vision devices they are issued. However, a night vision device designed for use by the general public would have to provide simple adjustments that can be readily operated by a variety of different users in a dark environment. Furthermore, a night vision device designed for use by the general public would also require various adjustable optical characteristics that would be easy to operate and adjust. Such a consumer oriented night vision device would have wide ranging application in regard t6 nighttime marine piloting, nighttime security, surveillance, hunting, fishing, backpacking, navigation, underwater vision, search and rescue and law enforcement.
ITT Corporation, the assignee herein, manufactures many night vision devices for various applications. Night vision devices for military applications are exemplified by U.S. Pat. No. 5,084,780 to Phillips entitled TELESCOPIC SIGHT FOR DAY/NIGHT VIEWING and U.S. Pat. No. 5,029,963 to Naselli entitled REPLACEMENT DEVICE FOR A DRIVER""S VIEWER. ITT Corporation, also has designed handheld night vision binoculars devices. Such a binocular device is exemplified in U.S. patent application Ser. No. 07/954,006, entitled CONSUMER NIGHT VISION VIEWING APPARATUS and filed on Sep. 30, 1992. In this application, a night vision binocular device is disclosed having simplified adjustment controls, interpupillary adjustments and diopter cell focus adjustments. Related optical components that can be utilized in the construction of night vision binocular devices are shown in U.S. patent application Ser. No. 08/039,755, now U.S. Pat. No. 5,317,397 entitled DIOPTER CELL ASSEMBLY FOR A BINOCULAR VIEWING SYSTEM, and U.S. Pat. No. 5,117,553, entitled COLLIMATOR FOR A BINOCULAR VIEWING SYSTEM, both of which are assigned to the assignee herein. These references show a diopter cell design and a collimator lens assembly for night vision binoculars, respectively. The assignee holds many other patents and applications related to image intensifier tubes and related devices which are of interest in regard to the present subject matter.
As has been previously mentioned, an important application for publicly available night vision devices is on recreational boats. Boats often run at night utilizing only their running lights for illumination. The use of night vision devices by the pilots of boats will greatly increase visibility, resulting in less nighttime collisions and similar accidents. The night vision binoculars will enable boaters to identify objects detected on radar, see land marks, read channel markers, detect navigational hazards, identify approaching vessels and much more. The environment of a recreational boat is less than ideal for a sophisticated electro-optical device such as a handheld night vision instrument. To survive in such an environment, the night vision instrument must be capable of withstanding large temperature changes, impacts, and must be hermetically sealed to withstand the high humidity environment and the possibility of being dropped into the water. Furthermore, since most recreational boats are small, inexpensive craft, the night vision device must provide the same performance as military specification night vision devices but at a greatly reduced cost so as to be affordable to the average boater.
It is therefore the object of the present invention to provide a night vision device that is easy to hold, easy to operate, water proof and provides the same performance as military night vision devices at a greatly reduced cost.
It is a further object of the present invention to provide component parts for the above-mentioned night vision device that are easy to manufacture and assemble, thereby further reducing the cost of manufacturing the night vision device.
The present invention is a night vision binocular assembly capable of converting low intensity light and infrared energy into a visible image. The night vision binocular assembly includes at least one objective lens assembly, image intensifier tube, collimator lens assembly and diopter cell assembly encased in an easy to ASSEMBLE waterproof housing. The objective lens assembly, image intensifier tube, collimator lens assembly and diopter cell assembly are all supported by a common optical base or bed structure within the housing. As a result, variations caused by thermal expansions and contractions are evenly distributed among the various optical elements, thereby preserving a predetermined optical relationship between those elements.
Simple button controls are used to operate and adjust the night vision binocular assembly. The button controls include an on/off switch, a brightness switch and a focus switch, all of which being surface mounting switching elements that are disposed on a common circuit board within the binocular housing. An elastomeric planar sheet having domed sloped integral switching actuating projections is disposed between the circuit board and the interior of the binocular housing. The circuit board is affixed to the interior of the binocular housing in a manner that engages the elastomeric structure. The elastomeric structure is glued by means of a waterproof epoxy or adhesive to the internal surface of the housing and is held and maintained in position by a plurality of pegs extending which align the elastomeric switch sheet with the circuit board. The domed projections of elastomeric structure extend through apertures in the binocular housing creating both a fluid impermeable seat with the housing and with the domed projections providing a means for the tactile engagement of the switching elements on the circuit board.
The present invention night vision binocular assembly is manufactured in a manner that promotes both ease of use and case of assembly. The primary optical elements of the night vision binoculars all interconnect onto the common optical base or bed structure with a minimal number of mechanical fasteners. The diopter cell assemblies require no mechanical fasteners in their assembly and the binocular housing can be assembled to be water tight without the use of a gasket. As a result, the present invention night vision binoculars can be manufactured and assembled in a highly reliable and cost efficient manner, thereby making the night vision binoculars affordable to the general consuming public.